Shock-absorber



L W.BLACKLEDG&

SHOCK ABSORBLTR.

APPLICATION FILED DEc.2s,191i.

1,393,938. Patented Get. 18, 192L 2 SHEETS-SHEET l.

`J. W. BLACKLEDGE.

SHOCK ABSORBE APPLICATION HL ED DEC 26' 1917.

Patented 0st. 18, 1923 2 SHEETS-SHEET 2.

UNITED STATES PATENT FFICE.

SHOCK-ABSORBER.

Specicaton of Letters Patent.

retreated oet. is, rear.

Application led December 26, 1917. Serial Eo. SfZGl.

To all whomY it may concern Be it known that I, JOHN W. BLACK- LEDGE, a citizen of the United States, residing at Chicago, in-the county of Cook and State of Illinois, have invented certain new and useful Improvements in Shock-Absorbers, of which the following is a specificaltion.

My invention relates to shock absorbers, andvhas for its particular object the provision of means whereby the vibration is reduced and jolting removed in vehicles, and

. is adapted particularly forautomobiles.

Another object of my invention is the provision of a .shock absorber which can be easily attached to a vehicle, is simple and efficient in operation, and4 is adapted to be applied to any make or manufacture of ma chine.

Another and further object of my inven'- tion is the provision of a shock absorber wherein the shocks incident tothe reaction of the springs Will be taken up, while there Will be no resistance against the compression of the springs. .v

My invention also provides for an increased resistance as the distance traveled by the springs on the recoil movement increases.

A further object of my invention is the provision of adjusting means in the shock absorber, whereby the resistance can be increased or diminished at will, and will also permit the springs of the vehicle to be freely compressed but which will resist the rebound on recoil of the springs from any degree of compression.

lvi'y invention Will be further and better understood by reference to the accompanyino drawings, in Whichfigure 1 is a vertical sectional' View through the center of my improved shock absorber;

Fig. 2 isa side elevation showing the cam and spring arrangement of one form of my invention;

Fig. 3 is a vertical sectional view showing a modified form of my invention;

Fig. t is a vertical sectional view on the line 1 4 of Fig.' 5 showing a slightly different arrangement of the ionic shown in Fig.

and.

l11 is a bracket attached to the flange 12 of the automobile frame by means of a bolt 13 having threaded engagement with the bracket 11. Rotatably mounted upon a spinl die 14 is a drum 15. The drum 15 consists of a rim portion 16, a web portion 17, and a hub 18. Around the hub portion 18 of the drum 15 is placed a spring 19, which may be either a torsion or clock spring, one end of which is inserted in an aperture 2O in the bracket 11, the other end of the spring being attached to a pin 21 inserted in an aperture in the outer portion of the web 17 of the drum 15.

The spindle 1li is held in threaded engagement with the bracket 11 and as an additional means of securing said spindle 14 in position and against rotation a pin 22 is inserted therethrough which also passes through an aperture in the bracket 11. Toward the outer end of the spindle 14.- is mounted a cam member 23, the portion of the spindle 14 upon which the cam member 23 is mounted being square to prevent ro tation ofthe cam member 23. Having threaded engagement with the outer end of the spindle 14 is a nut 24 which holds the cam member 23 and the drum 15 securely in position. Secured to the rim 16 of the drum 15 by means of rivets 25, 25, or other suitable means is a flexible strap 26 which encircles the drum 15 two or more times as may be.

desired, the end of the strap 26 being looped and fastenedv around the axle 27 of an automobile or to some other portion of the vehicle by any suitable fastening means, as 28. Attached to the inside of the rim 16 by means of rivets 29, 29, is a leaf spring 30, the free end of which is turned backward and is curved so as to conform to' the outside contour of the cam member 23 and bears against the outside surface of the cam member. Attached to the rim 1G of the drum 15 by means ofthe rivets 29,. 29, which secure thespring 30 in position is another leaf spring 11. the free end of whieh is in frietional engagement with the folded end of the spring ill) and serves to inerease the frietion between the eani 2? and the spring 11). The eam 221 has an ofl'set or shoulder portion 32, whieh. when the shoek absorbei' is being applied to the maehine, will abut against the folded end of the spring -ihthiis preventing the spring 1f) from revolving the drinn 15 indefinitely when the deviee is not in use or the di'iini is left unrestrained.

The effeet of folding the. end of the` spring $10 upon itself is to develop a brake shoe 30 and to inerease the radial resilieney thereof. 1t will be seen that the salient point of the eam 23 is so related to the wall 16 of'tlie drinn that it develops a spaee A laitween the eam and the wall whieli is less than the radial dimension of the spring 3() at the brake slioe 30", so that this folded end will erowd into the spaee if the drinn rotates a sufiieient distanee or if there is an extensive rebound of theI vehiele body, and thereby develop a yielding or shoek absorbing limiting stop in the aetion of the absorber. The folded endsi-EUl of spring EN) also afford an iulvantageoiis bearing for the reinforeing bladel 31.

rl`he drinn 15 may also be rotated so as to wind up tlie spring 1f) to any degree of tension prior to the attaehment of the deviee to an automobile. or afterward by unfastening the strap 26 and giving it another turn around the drum. Should the strap 26 beeoine broken` the folded free end of the spring 5i() would abut against the shoulder 32. pi'eventiiig the drum 15 from revolving.

lt will thus be seen that as the springs of an automobile are eoinpressed the drum 15 will revolve by reason of the l'oree exerted upon it by the spiing 111. keeping the strap 26 taut at all times until the extreme point. of compression of the springs is reached, and as the springs rei-oil the drum 15 will revolve. while the eam 2fat all times remains stationary. As the drum 15 revolves on the reeoil of the automobile springs the folded end of the spring 210 will travel around the eam 23 toward lthe highest point of the eani, and thus the amount of frietion, and consequently the'amoiint of'resistanee` will he increased as the distanee of the travel of the springs-is inerea'sed on their recoil movement. i

It is well known that the type of springs used on an automobile wil/l never break under compression, but breakage always oe` curs on the rebound, and thus my invention will serve not only to lessen the slioek of the recoil of the automobile springs but also to prevent breakage of the springs.

Fig. 3 shows a modified form of my inventlon wherein the drum 15 is mounted upon a spindle 35 formed integral With a braeket member $13, this member also having a pair of lip portions 34 adapted to fit over the flange portion 12 of theI automobile frame 1t). A bolt 13 is inserted through one of the portions 34 and serves to elamp the braeket member 321 to the 'automobile frame. A\.ease 3G ineloses the drum 15 and is held in position by means of a nut 37 having threaded engagement with the end of the spindle portion 35. 'lhe web 17 of the driinir 15 is disposed angularly instead of vertieally, as shown in l"ig. 1. llneireling the hub portion 18 of the drinn 15 is the spring 1f), arranged in praetieally the same manner as shown in Fig. 1, one end of .wliieh is seeured tothe pin 21 inserted in .the outside portion of the web 1T of the drum 15, the other end of the torsion spring being seeured to a pin 3f) inserted through a washer 4() and into the spindle 35. 'lhe spring 1f) in this form is plaeed on the opposite side of the web 1T and differs in this regard from the form shown in Fig. 1. llneireling the drinn and having onel end seeured to the drinn in the saine maniu as shown in Fig. 1 is the strap 213, whieh passes through an opening in the rase 113 and has its other end seeured to the axle or to some. part ol' the frame o1 an automobile. Mounted within a porke-t 252-1" and projecting inwardly against the web 17 formed in the braeket portion 2121 of the di'iiiii 15 is a brake member-11. whieh`is held in frietional engagement with the web 1T of the drum 15 by means of a eoiled spring 42. ly meansl of a bolt 43? having threaded engagement with the braeket member $14 thel desired v pressure is seeured upon the brake member 41. A\ washer 44 having a projeeting portion l5 thereon around whieli one end of the spring 42 lits is interposed between the bolt 425 and the spring 42. llie brake mem- 4bei' 41 also has a projecting portion 46. around whieh the opposite end of the spring lits, and thus" the spring 42 is held seeurely in position. Slight annular projeetions 4T, 47, on the web 17 serve to retain the brake member 41 in proper position. A washer 4H is plared between the hub 18 and the braeket 325 on the inside. and another washer 41) is plat-ed over the spindle 215 at its outer end and between the member 4f) and the ease 16.

lt will thus be seen that as the drum 15 is rotated the frietion on the web 17 of the drum 15 and the brake member 41 will be inereased, until the drum 1.5 has been rotated a half turn, but l have found in praetiee that even under the most severe jolting and shoeks the drum will travel a little more than one-third of an are of a eirele. And of course the drum can be'rotated in this form until the spring 19 is under considerable tension the Same as the type shown in Fig. 1.

ln Figs. 4 and 5 I have shown a further modification wherein the same general arrangement ot the parts as that shown in Fig. 3 is followed, with the exception that the bracket member 33 is ot a slightly ditt'erent form and the case 36 is omitted. In this form the web 17 ot' the drum 15 is vertical instead of being disposed angularly as in Fig. 3. An annular brake member 50 one end ot which is secured to the web 17 by means of bolts 51, 51, the other end being free is placed alongside ot the web 17, the plane ot the brake member 50 being angularly disposed with respectto 'the plane of 'the web 17. oil springs 52, 52, ot suitable lengths having seats formed in the web 17 and the brake member 5() are interposed between the brake member and the web 17 and hold the brake member 50 at the proper angle and also serve as cushioning means between the web 17 and the brake member 50. Having threaded engagement with the bracket 33 is a bolt 53 the head of which may be enlarged or spread in any manner desired to 'aitord a large 'friction surface between the head of thc bolt 53 and the brake member with which it contacts. lt will be understood therefore that as the drum 15 is rotated the brake member 50 will also be rotated with a constantly increasing amount of resistance until the limit of expansion of the automobile springs is reached, when the drum will return to its normal position, and ot course the bolt 53k can be adjusted so as to put any degree of pressure upon the brake member 50 that may be desired. l

lt may be that in some instances it will be desirable to omit the Jfriction members and rely upon the resistance of the spring which, as heretofore explained, can be set to any desired tension, and such moditi `ation I consider within the scope ot my invention.

lWhile I have described more or less precisely the details of construction, l do not wish to be understood as limiting myself thereto, as l contemplate changes iii form and the proportion of parts and the substitution of equivalents as circumstances may Suggest or render expedient without departing from the spirit ot my invention.

Vlhat claim is:

1. A shock absorber comprising.;` a drum, an attaching member upon which said drinn is mounted to rotate, a tension member wound upon said drum and adapted to impart rotation thereto in one direction, a spring adapted to impart rotation to the drum in the direction to rewindvthe tension member thereon, and coacting braking members'carried, respectively, by the attaching member and the drum; said braking members being constructed to develop an increasing resistance to the rotation of the drum imparted by the unwinding of the tension member, and to diminish resistance to the rotation induced by the spi-'ng in rewinding the tension-member.

2. A shock absorber comprisingn drum, an attaching member upon which said drum is mounted to rotate, a tension member wound upon said drum and adapted to impart rotation thereto in one direction, a spring adapted to impart rotation to the drinn in the opposite direction and rewind the tension member thereon, and a brake comprising trictionalmembers carried, respectively, by the attaching member and the drum; said 'trictional members being* constructed to incl-ease their friction and thereb v develop a progressively increasing resistance to the rotation of the drum imparted bythe unwinding of the tension member, and to diminish frictional resistance to the rotation induced by the spring in rewindiiig the tension member.

3. A shock absorber comprising an attaching member adapted tor'moimting upon one ot' two relatively moving parts, a drum rotatably mounted on said attaching member and adapted for connection with the other ot' said relatively nio-ving parts;v a tension member wound upon and adapted to impart rotation to the drum by unwinding theretrom, a spring adapted to rotate the drum in the direction to rewind the tension member thereon, and a brake `for resisting rotation olL the drum comprising a cam surface and a irictional brake member coacting with said cam surface, mounted one upon the attaching member and the other upon the drum; said cam surface being inclined in the direction to progressively increase the frictioiial braking etl'ect during the rotation imparted by the tension member and to relieve {rit-tional braking etect during the rotation wliicli. rewinds the tension member.

et. ln a. device of the class-descriliied, the combination ot a rotatable drum, a nonrotatable cam member, a spindle carrying the said drum and cam member,means tor attaching the Spindle to an automobile, a tension member winding on said drum, a leaf spring attached to the rim of said drum and in trictional Contact withvthe cani member,

. and a flexible connection whereby the said i drum is attached to another relatively movable part ot an automobile.

5. in a device ot the class described, the

combination ot a rotatable drum, a non-rotatable cam member, a spindle on which the rotatable drum and cam member are mounted, a bracket adapted to be attached to the trame of an automobile and carrying the spindle, a tension spring encircling the hub ot the drum and having one of its ends attached to the bracket and the other secured to the drum, a leat spring secured to the drinn having its free end folded back into rictional Contact with said cam, a reinforcing member for the said spring, and a flexible connection whereby the drum 1s secured to another relatively movable part of an automobile.

6. In a device of the class described, the combination of a rotatable drum, a non-rotatable caml member, a spindle on which the rotatable drum and cam member are mounted, a bracket adapted to beattached to the frame of an automobile and carrying the spindle, a tension spring encircling the hub of the drum and having one of its ends attached to the bracket and the other secured to the drum, a leaf spring secured to the drum having its free end folded -back into frictional contact with said cam, a second leaf Aspring secured to the drum having its free end engaging the free end of the firstmentioned spring, and a flexible connection whereby the drum is secured to another relatively movable part of an automobile.

7. In a shock absorber, carrying members one of which moves relatively to the other, braking members mounted upon the respective carrying members, comprising a cam surface and a shoe, one of which slides upon the other to develop camming action during such relative movement of the carrying members, means yieldingly opposing said camming action to develop resistance to said relative movement, and a wall opposite the salient portion of the cam surface coacting with one of said: braking members and -limiting said relative movement.

8. In a shock absorber, carrying members one of which moves relatively to the other, braking members mounted upon the respec tive carrying members and comprising a cam surface and a shoe, one of which slides upon the other during such relative movement of the carrying members, means yieldingly pressing the shoe against the cam surface in the direction to oppose the camming action, and a wall opposed to the salient portion of the cam surface and coacting therewith to develop a restricted space into which the shoe is crowded toward the end of said relative movement.

,9. In a shock absorber, a rotatable drum, a cam and coacting brake member, one of which rotates with said drum and the other of which resists such rotation.y and awall opposite said cam and developing with the latter a restricted space into which the brake member moves to increase its braking action; said brake member beingresilientin the direc-tion of confinement imposed by said space.

10. Ina shock absorber, a rotatable drum, a cam and coacting brake member, one of which rotates with said drum and the other of which resists such rotation, and a wall opposite said cam and developing with the latter a restricted space into which the brake member moves to increase its braking action; said brake member comprising a volute spring having vits end folded upon itself to develop a resilient shoe through which it bears upon said cam; and said cam and op-' posite wall being adapted to compress said folded end of the spring` as the latter enters the reduced space between the cam and wall. 11. In a shock absorber, a mounting, a friction memberA Supported by Said mounting and having a radially presented cam surface, a drum rotatably supported on said mounting and having a wall surrounding said cam surface, and a volute spring secured to the wall of said drum and constructed to bear upon said cam surface and frictionally resist the rotation of the drum.

12. In a shock absorber, a mounting, a friction member supported by said mounting and having a radially presented cam surmounting and having a wall surrounding said cam surface, and a volute spring secured to the wall of said drum and constructed to bear upon said cam surface and frictionally resist the rotation of the drum; said cam surface and the surrounding wall of the drum developing a reduced space near the salientpoint of the cam into which the bearing end of the spring is crowded bythe rotation of the drum.

13. In a shock absorber, a Xed cam having a radially presented camming surface, z' drum revoluble relatively to said cam, and a volute spring carried by said drum, extending circumferentially of the camming surface, and having its free end in frictional contact therewith.

14, In a shock absorber, a cam and its coacting brake shoe, and relatively rotatable members, one of which controls the cam and the other of ,which controls the brake shoe; said cam developing a gripping action upon said brake shoe: and the control of the brake shoe by said other member being resilient in the direction of relative rotation between the members.

15. In a shock absorber, a fixed cam having a radially presented camming surface, a drum revoluble relatively to said cam, and a volute spring carried by said drum, extending circumferentially of the camming surface, and having its free end in frictional contact therewith; the free end of said spring being folded upon itself to increase radial resiliency thereof.

16. In a shock absorber, a fixed cam having a radially presented camming surface, a drum revoluble relatively to said cam, and a volute spring carried by said drum, extending 'circumferentially of the camming surface, and having its free end in frictional Contact therewith; the free end of said spring being folded upon itself to increase radial resiliency thereof; and said spring having a reiforcing means bearing upon its folded en 17. A shock absorber comprisingl relatively7 rotatable members with means for imparting relative movement in one direction anda return spring for developing such relative rotation inthe opposite direction, and braking means tor resisting such relative rotation comprising a cfun surface and a, friction shoe bearing upon said @am surface;

said cam surface having a limiting shoulder which limits rotation between the cum and the shoe under the action of the return spring.

Signed at Chicago, in the county of Cook, and State ot' Illinois this 19th day of December, A. D., 1917.

JOHN W. BLACKLEDGE; t 

